Underreamer.



W. C. CUTLER.

UNDERHEAMER.

APPLICATION mnu MAn.6.19`n.

Patented Sept. 4, 1917.

` UNITED sTATEs PATENT oEEIoE.

WILLIAM G. CUTLER, 0F NORTH GLENDALE, CALIFORNIA.

UNDERREAMEB.

Application led March 6, 1917. Serial No. 152,855.

To all whom 'it may concern:

Be it known that I, WILLIAM C. CUnLER, a citizen of the UnitedStates,'residing at North Glendale, in the county of Los Angeles andState of California, have invented a new and useful Underreamer, ofwhich the following is aspecification.

This invention relates to devices for under-reaming a well below theinserted wellcasing, and an object of the invention is to simplify suchdevice.

Another object is to save material in the cutters so as to leave littlewaste after the bit part of the cutters has been used up.

Another object is to so construct thecutters that the reaming andworking of the cutters occurs under the most favorable condition for thecutters.

Another object is to shorten the Working levers of the cutters inrelation to the body of the reamer.

Another object is to shorten the bit part of the cutters below the bodyof the reamer, reducing the metal below the reamer body;

reducing the price of eXtra cutters, shortenf ing the lever between -thecuttingedge of the bit-part and the reamer body maklng it possible toprovide a proportionately long counter-lever toward the center of thereamer without having to use unnecessarily much metal in this part ofthe cutters, this again reducing the cost of extra cutters.

Another object is to bring the cutting edge of the cutters close to thereamer body while providing for a proportionately large expansioncausing the-pounding of the cutters to be taken up byfastrong solid endof the reamer body.

Another object is to eliminate all vconnecting rods` mandrels,spring-operated rods,

center blocks, and other operating partsused in otherl.under`reamers,the breaking1 of one of which usuall making the `whole deviceineffective, there 'y malnng thls'device yespeciallyT safe, besides bemgespecially inexpensive and simple, which in turn makes this devicedurable.

Other objects and advantages will appear in the following description,claims and accompanyingl drawing, in which-.-

Figure 1 is an elevation mainly 1n vertical mid-section of anunder-reamer embodying` my invention. j

Fig. 2 is a section on line 2-2 of 1.

Fig. 3 is a section on line 3 -3 of Fig. 1.

Specication of Letters Patent.

Fig. 4 is a similar view as Fig. 1, the cutters being slightly modified,the counter levers of the cutters in this figure being divided crosswiseinstead of in right angles to the cutting edges as shown in Fig. 1.

The lower end of the reamer body 1 is provided with a `bore 2 concentricto the device. A circular cavity 3 is bored out at a suitable distancefrom the lower end of the borre 2 forming an annular shoulder 4 at thelower termination of the cavity or recess 3. The cutters 5 and 6 areprovided with counter-levers 7 fitting in the bore of the reamer bodybelow the cavity or recess 3. A projection 8 is formed on the upper endof the counter-lever of each cutter normally enga ing with the annularshoulder 4 in the body. The lower end of the body terminates in a fullring shaped surface which is used as the pounding surface upon thecutters. The shoulder 9, formed on the cutters, rests smoothly againstthe full ring Vpounding surface of the body, while the cutting edges 10of the cutters project be- 'yo'nd the body outwardly from the centerofrthedevioe in a practically parallel line withfthe periphery of thecircular body. The 'projection 8 on the'- counter leverof the cutters iscut off on one side forming the abutment 11 allowingr the cutters toco1- lapse to the position indicated at 12 bringing' the abutment 11toward the shoulder 4 in the recess 3 ofthe body 1r'I` he cutters varethus mounted in the bo e of the body in pairs oscillating within the rewith the projections 8.rest1ng on the shoulders 4 in the' body. Aspring13 1s inserted into the bore 2'above the counter-`1evers 7, on top ofthe projections 8 forholding the cutters in operative position. Thecounter-levers are madelso much smaller'or narrower als to llow theprojections 8 on the counter-levers to pass" through the smaller lowerbore .14,

being the lower end 'of the bore 2 below the recess 3, a space 15 isthereby caused to re main as soon as the cutters are placed with thevprojections 8 on the shoulder 4, as shown in Fig. 2.

v'1"0 keep this space as narrow as possible and .to keep thecounter-levers as strongas possible, the counter-levers are bothtogether made slightly narrower than the diameter ofthe lower bore 14plus one width of the shoulder 4, `this making it necessary to insertone cutter first and placing same in 22, the chief point is to Aapart bysome means wh-ichwill keep the position with the projection 8 on theshoulder 4 and then insert the second cutter, as the space formed in thebore beside the first inserted cutter is then slightly larger than thethickness of the projection on the counter-lever of the second cutter.After having inserted both cutters and placed them in position with theprojections8 on the shoulder 4, there is just a space 15 left ofslightly, more than one width of the shoulder 4, as will easily' beunderstood.

To keep the cutters in this position, a distance plate or bar 16 is theninserted from below between the two cutters, and as this bar is notsubjected to any stress o r pressure, a very small screw or pin 17 issuicient to hold the bar in place..

To give a good seat for the spring 18, a ring 18 is inserted before thespring resting against the taper termination of the bore 2, saving atthe same time the work of having to be careful in drilling the bore and,by drilling, providing a square seat for the spring. Another ring orwasher' 19 is inserted below the spring on top of the cutters to providea smooth surface for the oscillating counter-levers of the cutters.

To assure a central location for the two counter-levers4 of, the cutterswithin the bore 1,4, projections or' bosses 20 are provided on the lower`end of the distance bar 16, for which suitable grooves21 are providedin the counter-levers of the cutters, see Fig. 1. But it will easily beunderstood that the distance bar can be made so much thicker and thegroove in thecounter-le`V rs can be of the width of the wholebar, Isindicated at keep the two cutters projections of the counter-levers ofthe cutters on the shoulder in the body. The tops 27 of thecounter-levers are sloping in normal position, eausings'the sprin 13 topress upon the highermost points o these sloping tops only. The abutment28, formed on the lower side of the projectie 8 is nearly parallel tpthe top, thereby br' gin only the middle of the projection inltouc withthe shoulder 4, whi e the sloping abutment 28 allows the spring to causea tilting movement on the counter-lever, thereby holding the shoulder 9ofthe cutter normally iessed against the ring termination of the ody.This tilting movement of the counter-levers and therewith the cutters,allows also a wear olf of the ring-termination of the body and oftheshoulders of the cutters as the spring willnaturally press thesloping levers and .thereby adjust worn off cutters to keep ressedtoward the. body preventing) a clic ing between the cutters and the ody,the usual cause of rapid wear off.

A slightly modified construction of my device .-is illustrated in Fig.4. Instead of dividing the counter-levers of the cutters in right anglesto the cutting edges of the cutters as illustrated and described in thefirst 'three figures, the counter-levers of the cutters in this modifiedconstruction are divided cross-Wise to the cutters or in nearly aparallel line between the two cutting edges. This modified constructionhas the advantage over the first described cutters, that a pair ofcutters can be turned out from a piece of flat steel of the width equalto the diameter of the cutting edge and of the thickness equal to thewidth of the cutters, and, after having turned off the cutters to thedesired dimensions, the finished piece is simply cut in two on the lines23, giving the two cutters for one reamer, as will easily be understood.The distance bar for this modified construction is a round bar 24 withthe ring 25, which fits slidingly in the bore 2, the ring being formedon the bar 24 or rigidly secu-red to the bar. For the bar 24 is asuitable recess bored into the end of the counter-levers while beingturned, as will easily be understood. In pressing the cutters into thecollapsed positions indicated at 2G, the bar 24: is moved upwardly, theonly difference of operation,the bar pressing on the centermost point.of the counter-levers within the recess, as will also easily beunderstood.

The bar24 rests in the recess on the counter-levers of the -cutterswithout being held in place by a pin or key for interconnection with thebody. The ring 25 simply slides withinrthe bore 2 of the bodycentralizing the bar and thereby holding the cutters in lace.

he foregoing will be suliicient to enable those skilled in the art tomake and use the invention which is understood to be only limited to astructure that is Within the spirit and scope of the following claims.

1. In an underreamer a body comprising a full circular bar having fromthe lower end upwardly a cylindrical main bore, the main bore beingenlarged at the lower end for a suitable dlstance forming a cylindricalbearing surface, the'main bore being further-more enlarged above thecylindrical bearing surface into a cylindrical cavity formin an annularshoulder between the cylindrical bearing .surface and the cylindricalcavity, cutters engaging with the body, and operating lmeans disposedbetween the body and the cutters within the 2. In 4an underreamer a bodybeing of a` full circular shape on the outside .and

`having a concentric bore from the lower end upwardly, lthe bore beingenlarged at the lower end for a suitable distance formdrical bearingsurface forming an annular shoulder above and adjacent to thecylindrical bearing surface in a plane at right angles to the axial lineof the underreamer, cutters engaging with the body, and operating meansdisposed between the body and the cutters within the body.

3. An under-reamer comprising a body having a concentric bore, the borebeing enlarged at a suitable distance from the lower end, forming anannular shoulder within the bore, cutters having counter-levers fittingin the bore terminating in projections adapted for engaging with theannular shoulder in the body, and a spring inserted into the boreseating on the counter-levers of the cutters.

4, An under-reamcr comprising a body of substantially full circularoutside having a recessed center bore, cutters having enlarged endstoward the center engaging with the body adapted for oscillatingmovement within the recessed bore, and operating means placed above thecutters within the body.

5. An under-reamer comprising a body of substantially circular crosssection all over the part of the body inclosing the operating parts ofthe reamer having a central bore, the bore in thc body being enlarged ata suitable distance from the lower end of the body upwardly, cuttershaving counter-levers projecting centrally and into the bore, thecounter-levers terminating in enlarged ends adapted to engage with thebody within the enlarged bore for oscillating movement, the Cuttershaving also cutting edges extending outwardly from the center of thebody in practically parallel lines With the periphery of the body, andoperating means inserted above the counter-levers of the cutters Withinthe body.

G. An under-reamer comprising a body of substantially circular crosssection all over the part of the body inclosing the operating parts ofthe reamer having a recessed center bore, cutters having counter-leversprojeeting toward the center and into the bore of the body foroscillating movement Within the recessed bore, a distance member mountedbetween the counter-levers of the cutters for holding the cutters withinthe enlarged bore yieldingly and swingably and operating means disposedbetween the body andthe cutters within the bodyl 7. An under-reamercomprising a body of substantially circular cross section all over thepart of the body inclosing the operating parts of the reamer having arecessed bore, cutters having means to engage with the'body within therecessed bore for oscillating movement, means for holding the cutters inposition within the recessed bore, and means for holding thc cutters inoperative position yieldingly and swingably.

8. In an underreamer a body of substantially circular outside all overthat part of the body which incloses the operating parts of the reamerhaving a central bore from the lower end upwardly, the bore beingenlarged at a suitable distance from the lower end to a suitabledistance upwardly forming a circular cavity or recessed bore above andbelow the remaining smaller cylindrical, central bore, cutters engagingwith the body, and operating means disposed between the cutters and thcbody within the body.

9. An under-reamer comprising a body having a concentric bore from thelower end upwardly, the bore being enlarged from a suitable distanceabove the lower end to a suitable distance upwardly forming an annularshoulder at the lower end of the cavity above the lower remaining centerbore, cutters having counter-levers projecting centrally and into thebore in the body, the counter-levers terminating in enlarged endsadapted to engage with the annular shoulder in the cavity, the enlargedends of the counter-levers on the cutters forming sloping tops in normalposition for allowing tilting movement by means pressing on thehighermost points of the sloping tops, the lower terminations of theenlarged ends on the counter-levers of the cutters forming also slopingsurfaces nearly parallel to the tops for allowing a tilting movement ofthese sloping surfaces on the annular shoulder in the cavity in thebody, and operating means inserted into the body above the sloping topsof the counter-levers on the cutters for automatically holding thecutters in operative position pressed against the lower end of the body.i

l0. An underreamer comprising a body having a concentric bore, the borebeing enlar ed at a suitable distance from the lower en forming anannular shoulder within the bore, cutters having means yieldably andswingably holding the cutters in the corr centric bore of the body onthe annular shoulder, and operating means inserted above the cuttersWithin the body.

l1. An underreamer comprising a body having a recessed concentric boreforming an 115 annular shoulder near the lower end of the body withinthe bore, cutters having means swingably and yieldingaly securing thecutters to the body when in operative position, and operating meansloosely inserted in the 120 body above the cutters.

12. An underreamer comprising a body having a' recessed concentric boreforming an annular shoulder near the lower end of the body within thebore cutters having 125 means swingably and yieldingly securing thecutters in the recessed bore of the body, and operating means hoidingthe cutters within the recessed bore of the body yieldingly andswingably,

llO

13. An underreamer comprising a body having a recessed concentric boreformin an annular shoulder near the lower end o the body within thebore, cutters having means engaging yieldingly and swingably with theannular shoulder 1n the bore of the body when in operative position, andoperating means securing t e cutters within the recessed bore so thatthe said cutters may yield and swing below the body when so engagedwithin the recessed bore.

14. An underreamer comprising a body having a recessed Iconcentric boreforming an annular shoulder near the lower end of the body within thebore, cutters having means engaging yieldingly and swingably with theannular shoulder in the bore of the body when in operative position,adistance member insertedbetween the cutters securing the cutters to thebody within the recessed bore so that the cutting edges of the cuttersmay swin automatically into operative position an also into collapsedposition while the distance member remains sta-` tionary, and operatingmeans disposed above the cutters within the body.

15. An underreamer comprising a body having a recessed concentric boreforming an annular shoulder near the lower end of the body within thebore, cutters having means engaging swingably with the annular shoulderin the body, a distance member inserted between the cutters allowing thecutters to collapse when pressure is applied to the cutters 1n adownwardly direction on the cutting edges and also allowing the cuttersto move automatically to the operative position when no ressure isapplied to the cutting edges of t e cutters in a. downwardly; direction,and a spring disposed between t e body and the cutters surrounding thedistance member within the body.

16. An underreamer comprising a body having a recessed concentric boreforming an annular shoulder near the lower end of the body within thebore, cutters having means en aging swingably with the annular shoulerin the body, a distance member secured to the body disposed betweenthe cutters allowing the cutters to freely swing into operative positionand into col apsed position, and means disposed in the body yieldnglyholding the cutters in operative posiion.

17 An underreamer comprising a body having a recessed concentric boreforming an vannular shoulder in the lower end of the bore, cuttershaving means engagin swingably with the annular shoulder in t e body, adiistance member removably secured to the bo y within the bore, thedistance member securing the'cutters swingably to the bodyV withoutbeing onnected to the cutters allowing the cutters to freel swing intooperative position and into co lapsed position, and

means di osed in the bore of the body yieldingly hol ing the cutters inoperative position.

18. In an underreamer, a cutter having a nearly semi-circular shank withthe flat face at substantially a right angle to the cutting edge of thecutter, a shoulder extending laterally from the shank nearly parallel tothe base line of the cutting edge, an abutment extending also laterallyfrom the shank above the shoulder in sloping relation tb the shoulderfrom about the middle of the nearly semi-circular shank extendingVslightly inclining upwardly in the opposite direction from the cuttingedge forming the engaging member of the cutter, and a top surface on theshank in nearly parallel line with the abutment.

19. In an underreamer, a cutter having a counter lever with a flat faceparallel to the center line through the cutter at substantially rightangle to the cutting'edge as seen in plan view, a shoulder extendinglaterall from the counter lever in practically para lel line with thebase lineof the cutting edge as seen in side elevation, an abutmentextending also laterally from the counter lever above the shoulder ininclined relation to the shoulder from the middle of the counter leverslightly rising toward .the side of the counter lever in the oppositedirection of the cutting edge forming the engaging member of the cutter,a top abutment on the counter lever in nearly parallel lines withtending rom the engaging abutment up-4 wardly toward the to abutment onthe same side of the counter ever with the cutting edge.

20. In an underreamer a cutter having a counter lever with a fiat faceat substantially right angle to the cutting edge of the cutter, anengagin abutment op osite to the flat face extending laterall rom thecounter lever forming a circum erentially channeled neck, and a shoulderextending laterally from the shank below the abutment and above thecutting edge.

21. An underreamer comprising a body .having a recessed concentric' boreforming an annular shoulder in ,the lower end of the bore, a pair ofcutters rojecting with the cutting edges outward y beyond andV in nearlyparallel lines with the periphery of the body having counter leversswingabl fitting in the bore of the body engaging with the annularshoulder, the line of division between the .counter levers of the twocutters being in right angles to the cutting edges, and operating meansinserted in the bore holdin the cutters in operative position.

22. n underreamer comprising a body having a recessed concentric boreforming an annular shoulder in the lower end of the bore.; a pair of.cutters 'rojecting with the ofthe cutters, and a spring disposed in theY cuttmg edges 'outward beyond and in body for automatically holding thecutters t nearly erallel lines wit the peripheryof inoperative positionin comblnation with the bodg7 having counter levers swingabl thedistance member.

5 fitting in the bore-of the bodyengaging Wit In testimon whereof I havehereunto set theA annular shoulder, and a distance memmy Khand at osAngeles, California, this ber vslidngrly inserted in the bore extending2'( th day of February 191 between the counter levers of the cutters sol WILIAM CQ CUTEER. that the cutters may collapse` and "swing Inpresence of- 10 back into operative position upon corre- LUomN GRAY,

spending pressure agemst the cutting edges EVALYN N. SPARKS.

